M-GRIN Aims to Simplify Specialized Optics

Advances in the design and fabrication of gradient index (GRIN) optics are leading to smaller, less complex optical assemblies and lower manufacturing costs for specialized optics.

“In the past century, every component of an optical system has become lighter and smaller, except the optics,” said Stefanie Tompkins, DARPA program manager. “The impact of smaller, lighter optics on anything used to focus light, from contact lenses and corneal implants to lasers and solar arrays, would be enormous.”

DARPA’s Manufacturable Gradient Index Optics (M-GRIN) program seeks to leverage these advances to make custom GRIN lenses readily available within the next three years.

Among the recent advances in GRIN lenses is a method for fabricating them from layers of polymer, creating a lens that can control the light within the lens along arbitrary paths, so the light no longer needs to travel in straight lines.

“GRIN optics can be shaped to fit a system, rather than making the system conform to the optics, resulting in reduced size, weight and assembly cost. For the first time, manufacture of just a few custom lenses can be made at any point during a high-volume run without increasing the unit cost,” said Tompkins.

The new GRIN fabrication technology lends itself to flexible and inexpensive manufacturing techniques, and the program seeks to develop a manufacturing capability while advancing GRIN lens design and fabrication technology.
The program kicked off the first phase in September 2010 and will conduct preliminary design reviews in the next month for two challenge problems: wide-field-of-view solar concentrators and lightweight night-vision goggles. Future work will emphasize manufacturability, with a goal of reaching low-rate initial production by September 2013.

For more information, visit: www.darpa.mil